reporter: at an oakland california poork built as a memorial to the '89 quake, david swartz of the u.s. geo logical survey remembers that for all the destruction, the epicenter of that quake was far away. >> 1989 was 70 miles south of the bay area proper. and we think our next big earthquake will occur right in the middle of the urban center. if you look at it that way, the hills are the east bay hills and the heyward falls runs to the base of the hill. >> reporter: the heyward fault is overdue. add the san andreas and a startling number of lesser-known faults, the san francisco region is ripe for quakes. >> we're surrounded by faults anywhere you go in the bay area. we jokingly like to say you can run but you can't hide. that's sort of the truth. >> reporter: the san andreas fault brought on the great san francisco earthquake of 1906. it's been estimated that 3,000 people died. that's the kind of quake, much bigger, much more destructive than the one in 1989, that seismologist figure could be on its way. >> we've estimated in the next 30 years a 63% chance, two out of three, that we'l